Pneumatic-despatch system.



P. R, SHILL. PNEUMATIC DESPATGH SYSTEM.

' APPLICATION FILED AUG.14, 1908. 939,872.

Patented Nov. 9, 1909.

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. P. R. SHILL. PNEUMATIC DESPATGH SYSTEM.

APPLICATION FILED AUG. 14, 1908. 939,872. Patented N0v.9, 1909.

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Patented Nov. 9, 1909.

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P. R. SHILL.

PNEUMATIC DESPA'IGH SYSTEM.

APPLICATION FILED AUG.14, 1908. 9893729 Patented Nov. 9, 1909.

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Patented Nov. 9; 1909.

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P. R. SHILL.

PNEUMATIC DESPATOH SYSTEM. APPLICATION FILED AUG.14, 1908.

939,872. Patented N019, 1909.

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P. R. SKILL.

PNEUMATIC DESPATUH SYSTEM.

APPLICATION FILED AUG.14, 1908.

Patented Nov. 9, 1909.

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UNITE STATES rAtrENr caries.

PERCY RICHARDSON SHILL, (3F LEYTONSTONE, ENGLAND, ASSIGNOR 01 ONE-FOURTH TO CHARLES WILLIAM BLUElVIEL, ONE-FGUBTH TO FRANK HENRY BLUEMEL, AND ONE-FOURTH T0 ERNEST ADOLPHUS BLUEMEL, WOLSTON, ENGLAND.

PNEUMATIC-DESPATCH SYSTEM.

Specification of Letters Patent.

Patented Nov. 9, 1909.

Application filed August 14, 1908. Serial No. 448,631.

To all whom it may concern:

Be it known that I, PERCY RICHARDSON SHILL, a subject of the King of Great Britain, residing at Leytonstone, Essex, Eng land, have invented a certain new and useful Pneun1aticDespatch System, of which the following is aspecification.

This invention relates to electrically-controlled pneumatic despatch-tubes, cash railways and the like, of the kind described in the specification of British Letters Patent No. 16650 of 1904, that is to say to systems in which there is a single tube forming a closed air circuit, and the said invention has for its chief object to simplify the construction of such systems whereby carriers of the same form can be used for all the substations, and the need for electrical contacts on the carriers is dispensed with.

The said invention comprises improved forms of transmitting and receiving apparatus for use at the central and sub-stations, improvements relating to the switches used for switching the carriers into the sub-stations, and an improved arrangement of a single tube air circuit to form two or more systems, all substantially as hereinafter described with reference to the accompanying drawings.

In these drawings :Figure 1 is a front elevation with the cover removed showing the inlet or sending terminal at the central station. Fig. 2 is a rear elevation partly in vertical section, of the said sending terminal. Fig. 2 is a similar view to Fig. 2, showing the operative parts in the position which they assume when a carrier is leaving the sending terminal. Fig. 3 is a transverse vertical section on the line A B, Fig. 1, looking toward the left of said figure. Fig, 4 is a transverse, vertical section on the line A B, Fig. 1, looking toward the right of said figure. Figs. 3 and 4; are respectively views similar to Figs. 3 and at, showing the operative parts in the position which they assume when a carrier is lying in the sending terminal ready for despatching. Fig. 4* is a perspective view showing the arrangement of the contact plunger and its carriage in relation to the switch-contacts and detent-bar. Fig. 5 shows on a smaller scale the general arrangement of the inlet or sending terminal and outlet or delivery terminal, and the connections with the blower at the central station. Fig. 6 is a front elevation, drawn to a smaller scale, showing the general arrangement at a substation. Fig. 7 is a vertical longitudinal section. (Figss'? to 13 are drawn to a scale larger than that of Fig. 6). Fig. 8 a vertical transverse section on the line C D,

-' Fig. 7, showing an electromagnetically-operated switch for diverting carriers from the .main pneumatic tube into a sub-station.

Fig. 9 is a vertical section of an outlet or delivery terminal for a carrier either at the central station or at a sub-station. Fig. 10 is a horizontal section on the line E F, Fig. 9, showing details of the outlet or delivery terminal. Fig. 11 is a side elevation, partly in section illustrating an inlet or sending terminal for the carriers at one of the substations. Fig. 11 is a similar view to Fig. 11, showing the parts in the position which they assume when a carrier is leaving the sending terminal. Fig. 12 is a vertical section on the line J K, Fig. 11, and Fig. 13 is a horizontal section on the line L M, Fig. 11, showing details of the inlet or sending terminal. Fig. 1a is a diagram showing the arrangement of the electric circuits. Fig. 15 is a diagram showing the arrangement of a single main pneumatic tube or conduit and blower controlling three systems each comprising a central station and a series of substations.

Like characters indicate corresponding parts throughout the drawings.

a. is a single pneumatic tube, which is arranged in a continuous circuit extending from the inlet to the outlet of a blower b, substantially as described in the specification of said former Letters Patent No. 16650 of 1904, or as shown in Fig. 15. v

Each station, whether central or sub-station, comprises an inlet and an outlet for the carriers. I will now proceed to describe the inlet or sending terminal at the central tion "ith reference to Figs. and 5. The inlet or sending terminal comprises a box or casing 0 through which extends a branch pneumatic tube a. In order to permit the insertion of the carriers, the tube a is pro vidcd at its upper end with a door (Z, turning about a pivot-pin c. Said door is drawn down on to its seat by a spring 0 arranged around the pin 6 and by cam surfaces (Z, d formed on the said door and on the upper end of the tube a. At a suitable distance below said upper end, greater than the length of a carrier, there is provided a trapdoor f, which extends into the tube a through a lateral aperture a and turns about a horizontal aXis f. This door when there is no carrier in the upper end of the tube a is brought into its raised position by means of a counterweight A detent g, pivoted at g and provided with a counterbalance weight g of non-magnetic material is provided for locking the door 7 in its raised position, so as to enable it to support a loaded carrier. This detent forms the armature of an electromagnet it, having pole-pieces 71' whereby it can be tripped, so as to release the trap-door f and allow the carrier to overbalance the weight 7 and fall down the lower part of the branch tube a, into the main air tube a, where it is acted upon by the air current produced by the blower Z). A closed easing surrounds the part of the tube a which is perforated to receive the door f and the levers hereinafter described. The sending terminals of the several substations are, as can be seen from Figs. 11, 12 and 13 constructed with substantially the same parts. In these, however, a liner tube a is provided, between the lower end of which and the entrance to the branch pipe a is a ga i The outlet or delivery terminal at the cen tral station is in series with the tube a as shown in Fig. 5, those at the sub-stations are arranged in branch tubes The construction of the delivery terminal or outlet is the same for all stations and comprises a casting a Figs. 9 and 10, the carrier outlet from which is furnished with a door moving transversely in guides 76 and normally retained in its closed position by means of a bent lever on, m pivoted at of. The arm 'm of this lever is made in the form of a counterweight, while the arm m is connected at its lower end to the door 70 by means of a slot m engaging a pin 70 on the door 70. The arm m is moreover curved on its upper surface, so as to enable it to engage smoothly with the leading end of a carrier and to be swung laterally thereby, so to open the door it: and allow the carrier to pass out. When the carrier is clear of the arm m and door in, the said door is immediately closed by the weighted arm m. The air passes from the casting a through an opening at the side thereof to the blower Z) in the case of the central station delivery terminal, and to the adjoining sending terminal in the case of a sub-station. The connection between the sending and delivery terminals at a substation is through a branch pipe (4*. And preferably the air is carried around a channel 07 in the sending terminal so as to avoid fouling the electromagnet h and connected parts. The branch air-pipe a leading from the main air-pipe a to a sub-station is controlled by a switch a, Figs. 6, 7 and 8, which is actuated electromagnetically from the central station as hereinafter described when it is desired to divert a carrier from the main tube a into the branch tube a of the particular substation in question. The switch a is pivotally mounted at n in a closed casing 0. The said switch is normally retained out of the path of the carriers in the main tube by the action of gravity and is raised to divert a carrier into the branch-tube a by means of an electromagnet 70 having an armature p pivotally mounted at p and engaging at its free end in a fork n on the switch a. A weighted arm n on the switch a partly counterbalances'the said switch, so

as to reduce the work to be done by the electromagnet p. The switch a is retained in its raised position by means of a gravity-pawl Q engaging with the free end of said switch, so as to render it unnecessary for the current to circulate through the coils of the electromagnet p for the whole time that the said switch is to be maintained in its raised position. The pawl g is combined with the armature of an electromagnet 7 whereby it may be tripped from the central station as hereinafter described. The switch a is moreover provided at its free end with an areshaped plate or valve 16 which closes the thoroughfare of the main air pipe a beyond the switch n when said switch is raised and thus causes the air-current to be diverted into the branch passage or by-pass a (L3, (4, a from which it returns to the main tube a at the farther side of the sub-station.

The selection of the particular sub-station to which a carrier is to be sent from the central station is effected by means of the following electrical system :A multiple-way selector switch comprising a number of insulated contact-springs s, 8 (Figs. 1, 3 and a) each connected by a line-conductor s (Fig. 14) to one of the switch-electromagnets 2?, the several circuits being completed through a common return 6, a suitable electric generator u, a conductor 7), a time switch having an uniformly rotating contact-piece w and stationary contacts w, 'w', the releasing electro-magnet h for the trapdoor f at the central station, a conductor a? and a bus bar y bearing a number of con tact-springs 3 3 respectively arranged opposite the contact-springs a, 8. Any pair of springs s, y can be brought into contact with each other by means of a plunger .2 which can be pushed inward to press the springs s, y together. Opposite each pair of springs s, y is an opening 30 in a front cover plate 31 through which the plunger 2 passes and by which the plunger is caused to register with the springs s, 3 The plunger 2 is mounted in a carriage 1 sliding transversely on a longitudinally slotted guide-bar 2 and is provided with an undercut-head 2. This plunger is normally returned to its outermost position by a spring 2 butwhen there a carrier in the part of the tube a" above the trap-door f, the plunger 2 is retained in its innermost position by means of an insulated detentbar 3 which is mounted on a bail pivoted at 5 to the casing This bail is connected by a pivoted link 6 and a slot 7 and pin 8 to an arm 9 fixed to an arbor 1O rotatably mounted in the casing The said bail in its normal position stands directly in front of the end of the plunger 2 (Fig. 3), so as to prevent the said plunger from being pressed in. The arbor 10 has fixed thereto a lever 11, which is arranged inside the easing and the lower end of which normally extends through a slot into the tube a, as shown in Fig. 3, so as to be pressed outward by a carrier introduced into the upper end of the tube a and at the same time to move a stop 12 fixed on the upper arm or end of the lever 11 into the thoroughfare of the tube a above the carrier, thereby preventing the introduction of further carriers into said tube. The arbor 10 also has fixed thereto, outside the casing 7', an arm 13 hearing a projection 1st which, when the lever 11 has been oscillated by a carrier inserted into the tube a as above described, moves over and in front of a similar projection 15 on the bail 4 the said bail only being lifted by the link 6 to such a height as to permit the passage of the projection 1 1 over the projection 15. II" the head .2" of the plunger 2' be now pressed beneath the detent-bar 3 so as to further raise the bail 4:, the projection 15 will be brought into the path of the projection 1t thereby preventing the return of the lever 11 until the bail 1 been raised as hereinafter described and the plunger .2 released and thus allowed to return to its normal position.

For raising the bail 4, an electromagnet 17 is provided, which is connected to the electric generator a through the conductor 2., and through the contacts 70 Q0 of the timing switch, (Fig. 14) the conductor 18 and a switch 19, 20, the movable arm 20 of which is fixed on an arbor 21 pivotally mounted in the casing The arbor 21 bears a weighted arm 2, which normally holds the switch arm 20 in such a position that the circuit is closed, and a second arm which is arranged inside said casing and extends into the path of the carrier in the upper end of the tube 0'. hen a carrier is brought into position on the trap-door 7, the arm is moved so as to separate the switch-con tacts 19, 20. .Vhen, however, the carrier has moved past the trap-door and the arm has been released, the arbor 21 will be turned by the weighted arm so as to close the switch 19, 20, so that when the movable contact 10 of the timing switch connects the contacts 10 1.0 the electromagnet 17 will lift the bail t and detent bar 3 by means of armature pieces 24, 21 thereon and thus allow the plunger 2 to be drawn out by its spring .2 as the bail 4 is immediately released by the electromagnet 17 by reason of the contact in leaving the fixed contacts 20 10 the projection 14 will be free to move past the projection 15 and allow the lever 11 to return to its normal position, thus withdrawing the stop 12 from the thoroughfare of the tube a and thereby permitting the insertion of another carrier. The releasing electromagnets 71-, it for the sub-station. inlet, apparatus and also the releasing electromagnets 1', r for the switches a, n are connected across the conductors t, 18, so that these electromagnets are simultaneously energized when the contact 11* of the timing switch passes over the fixed contacts 10*, 11-

The operation of the improved system is as follows: Assuming carriers to be resting on the trap-doors f, f in the sending terminals at the central station and at one or more of the sub-stations, and the plunger at the central station to be arranged opposite the desired pair of springs s, y, and to be pressed in (Figs. 3 and P) so that the switch a at the corresponding sub-station will be raised by its electromagnet p, then as soon as the contact Z0 of the timing switch moves past the fixed contacts 'w, to, the inlet releasing magnet 7L at the central station will be energized and will release the carrier (Fig. 2) and allow it to pass down the pipe a to the main tube a and thence to the desired sub-station where the switch a is raised. Here the carrier will deflect the lever m and valve l: of the delivery terminal and pass out into a suitable receptacle. On the movable contact to reaching the fixed contacts 20 20 the releasing electromagnets h, h of the inlet doors f, f at the substations (Fig. 11 and also the releasing electromagnets r, r of the switches a, 77. will be energized, so that the carriers in the sending terminals at the sub-stations will be admitted into the main tube av and any switch it, which may be raised will simultaneously be lowered to clear the passage through the main tube a and thus allow all the carriers to pass along the tube a and out at the delivery terminal at the central station. Thus there is no interference between the carriers travcling from and to the central station.

In Fig. 15, an arrangement is shown in which three tems with their central sending and delivery terminals are arranged in series on a common main tube 1:. In this case, the several releasing electroinagnets of the several systems are operated successively, for which purpose the con -ts ac, in. 20 w thereof are preferably arranged at regular intervals around the movable member of the timing switch, as indicated in Fig. 14*. If desired two systems or four or more systems may be controlled from a single blower and timing switch.

What I claim is 1. An electrically-controlled pneumatic despatch tube, cash railway or the like, comprising an air-tube, an air-propelling device connected to said air-tube, a multipleway electric selector-switch, an electric generator, electromagnetically controlled carrier-switch-apparatus at the several stations, electrical connections between said carrier-switch apparatus, said electric generator and said selector-switch, a plunger, for actuating the contacts of said multipleway selector-switch, a detent-bar for holding said plunger in its pressed-in position, an electromagnet for disengaging said detentbar from said plunger, a releasing switch for connecting and disconnecting said disengaging electromagnet to and from said electric generator, electric connections between said electric generator, said electromagnet and said releasing switch and means controlled by a carrier in a sending terminal of said air-tube for opening and closing said releasing switch.

2. An electrically-controlled pneumatic despatch-tube, cash railway or the like, comprising an air-tube closed on itself, substations branching from said air-tube, an airpropelling device connected in the circuit of said air-tube, carriers adapted to move in said air-tube, carrier-switches serving as airvalves and adapted to'defiect said carriers into the substations, electromagnets for moving said carrier-switches into their operative positions,a manually-operated multiple-way electric selectorswitch, an electric generator, electric connections between said electric generator, said electromagnets and said selector-switch, sending terminals comprising means for retaining the carriers, electromagnets for releasing said carrierretaining means, electromagnets for releasing said carrier-switches and an electric time-switch for periodically closing interruptions in the circuits of said electro-magnets.

3. In an electrically-controlled pneumatic despatch-tube, cash railway or the like, a multiple-way electric selector-switch and central-station carrier-despatching apparatus comprising a series of spring contactpieces, a plunger adjustable laterally to register with any one of said contact-pieces, a spring urging said plunger away from said contact-pieces, a detent-bar adapted to hold said plunger in engagement with any one of said contact-pieces, an electromagnet for disengaging said detent-bar from said plunger, an electric generator, an air-tube, and means for closing the circuit of said electromagnet when there is no carrier in the sending terminal of said air-tube and for onening said electric circuit when a carrier is in said sending terminal.

4:. In an electrically-controlled pneumatic despatch-tube, cash railway or the like, a multiple-way electric selector-switch and central station carrier despatching apparatus, comprising a series of spring contactpieces, a plunger adjustable laterally to register with any one of said contactpieces, a spring urging said plunger away from said contact-pieces, adetent-bar adapted to hold said plunger in engagement with any one of said contact-pieces, an'electromagnet for disengaging said detent-bar from said plunger, an electric generator, an air-tube, a switch controlling the circuit of said electromagnet, and a weighted operating lever for said switch, said lever extending into the sending terminal of said air-tube in such a manner as to open the switch when there is a carrier in said sending terminal and'to close said switch when said carrier has been despatched.

5. In an electrically-controlled pneumatic despatch-tube, cash railway or the like, a multiple-way electric selector-switch and central station carrier despatching apparatus, comprising a series of spring contactpieces, a plunger adjustable laterally to register with any one of said contact-pieces, a spring urging said plunger away from said contact-pieces, a detent-bar adapted to hold said plunger in engagement with any one of said co-ntactpieces, an electromagnet for disengaging said detent-bar from said plunger,

an electric generator, an air-tube, means for closing the circuit of said electromagnet when there, is no carrier in the sending terminal of said air-tube and for opening said electric circuit when a carrier is in said inlet end, a pivoted lever, a link pivotally connecting said lever and said detent-bar through a pin and slot connection, and an arm fixed to said lever and extending into the sending terminal of said air-tube so as to cause the detent-bar to be supported directly in the path of said plunger when there is no carrier in said sending terminal and to be supported in position for retaining said plunger in its pushed-in position when a carrier is in said sending terminal.

6. In an electrically-controlled pneumatic despatch-tube, cash railway or the like, a multiple-way electric selectorswitch and central-station carrier-despatching apparatus comprising a series of spring contactpieces, a plunger adjustable laterally to register with any one of said contact-pieces, a spring urging said plunger away from said contact-pieces, a detent-bar adapted to hold said plunger in engagement with any one of said contact-pieces, an electromagnet for disengaging said detent-bar from said plunger,

an electric generatonan air-tube, means for i closing the circuit of said electromagnet when there is no ca rier in the sending terminal of said air-tube and for opening said electric circuit when a carrier in said sending terminal, a pivoted lever, a link pivotally connecting said lever and said detent-bar through a pin and slot connection, a stop fixed to an upper arm of said lever and extending into the sending terminal of saio air-tube so as to cause the detent-bar to be supported directly in the path of said plunger when there is no carrier in said sending terminal and to be supported in position for retaining said plunger in its pushed-in position when a carrier is in said sending terminal, and an arm forming an extension of said pivoted lever, said stop, when there is a carrier in said sending terminal, projecting into said sending terminal on the outer side of said carrier so as to prevent the insertion of another carrier until the one already in said sending ter minal has been despatched.

T. In an electrically-cont-rolled pneumatic despatch-tube, cash railway or the like, a sending terminal comprising a series of soring contact-pieces, a plunger adjustable laterally to register with any one of said contact-pieces, a spring urging said plunger away from said contact-pieces, a detentadapted to hold said plunger in engagement with any one of said contact pieces, an electromagnet I'or disengaging said detent-bar from said plunger, an elec tric generator, an air-tube, means for closing the circuit of said electromagnet when there is no carrier in the sending terminal of said air-tube and for opening said electric circuit when a carrier is in said sending terminal, a pivoted lever, a link pivotally connecting said lever and said detent-bar through a pin and slot connection, an arm fixed to said lever and extending into the sending terminal of said air-tube so to cause the detent-bar to be supported directly in the path of said plunger when there is no carrier in said sending terminal and to be supported in position for re taining said plunger in its pushed-inposition when a carrier is in said sending terminal, a stop-arm fixed to said pivoted lever, a stop on said detent-bar for coacting with said stop-arm when a carrier is in the sending terminal of the air-tube and the plunger has been pushed in, so as to prevent the return of said pivoted lever, detent lever and plunger to their normal positions until the detcntbar has been attracted by its controlling electromagnet.

S. In an electrically-controlled pneumatic despatch-tube, cash railway or the like, an air-tube closed on itself, an air-tube, a substation arranged as a loop on the main airtube, a switch for diverting carriers from the main air-tube into said loop, automatic l l l troinagnet and said detent-electromagnet witn said electric genera-tor, a predetermined.

interval of time being allowed to elapse between said connections.

9. A singletube air-conduit closed on itself and arranged to form a plurality of electrically controlled pneumatic despatchtube, cash-railway or like systems, central and sub-stations for each of said systems, an e ectric generator, electromagnetically-controlled sending terminals for said stations, electromagnetically controlled carrierswitch setting and releasing devices for the sub-stations, an electromagnetically-controlled electric selector-switch arranged at each central station, and an electric timing switch which momentarily connects said electric generator simultaneously with the sending terminal for the central station of each system and the setting device for a carrier-switch and after a predetermined time momentarily connects said electric generator simultaneously with the sending terminals for the substations and the releasing devices for the carrier-switches of the sane system, the corresponding connections for the difl'erent systems being separated by predetermined intervals of time.

10. An elect-rically-controlled pneumatic despatch tube, cash railway or the like, comprising an air-tube forming a closed aircircuit, an air propelling device connected in said air-circuit, substations in the form of by-passes or loops on said air-circuit, electrically actuated carrier deflecting switches at said substations, a multiple-way electric selector-switch, detents or pawls for said carrier-deflecting switches, electric tripping devices for said detents or pawls, electrically-actuated sending terminals or carrierinlets, an electric generator, means for looking said selector-switch, an electrically-actuated release for said selectonswitch, electric connections bet-ween said electric generator and said electrically-actuated mechanism and a timing-switch controlling in terruptions in said electric connections.

11. A multiple-way electric selectorswitch for an electrically controlled pneumatic despatch tube, cash railway or the like, comprising a series of electric contacts, a plunger adjustable to register with any one of said contacts, a spring urging said plunger away from said contacts, a detentbar for holding said plunger in engagement with any one of said contacts, an electromagnet for disengaging said detent-bar from said plunger, an electric switch for controlling the circuit of said electromag net, an air-tube, a weighted operating lever for said swltch, sald lever normally extending into the sending terminal or inlet end of said air tube and closing said switch, a pivoted arm normally extending into the sending terminal or inlet end of said airtube, a lever fixed to said arm, a link pivotally connecting said lever and said detentbar through a pin and slot connection, a stop-arm fixed to said lever, a stop on said detent-bar for coacting with said stop-arm, and a carrier-stop forming an extension of the said arm in the sending terminal or inlet of said air-tube, substantially as and for the purposes hereinbefore described.

12. A multiple-way electric selectorswitch for an electricallycontrolled pneumatic despatch-tube, cash railway or the like, said switch comprising a series of movable electric contacts, a guide-frame, a carriage movable along said guide-frame, a spring-pressed plunger slidably mounted in said carriage, means for bringing said plunger into register with any one of said contacts, a detent-bar extending parallel to said guide-frame and adapted to engage a notch in said plunger when said plunger is in engagement with a contact, and an electromagnet for tripping said detent.

13. A multiple-way electric selectorswitch for an electrically-controlled pneumatic despatch tube, cash railway or the like, said switch comprising a series of electric contacts, a spring-pressed plunger adjustable to register with any one of said contacts, a detent-bar for holding said plunger in its pressed-in position, electromagnetic means for releasing said plunger, and an electric timing switch for controlling said releasing means.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

PERCY RICHARDSON SHILL. itnesses GEORGE HARRISON, ALEXANDER WV. ALLEN. 

